target = "https://www.rfc-editor.org/rfc/rfc8899#section-6.1.6"

# 6.1.6.  Handling of PTB Messages
#
# An application that is able and wishes to receive PTB messages MUST
# perform ICMP validation as specified in Section 5.2 of [BCP145].
# This requires that the application checks each received PTB message
# to validate that it was is received in response to transmitted
# traffic and that the reported PL_PTB_SIZE is less than the current
# probed size (see Section 4.6.2).  A validated PTB message MAY be used
# as input to the DPLPMTUD algorithm but MUST NOT be used directly to
# set the PLPMTU.

[[spec]]
level = "MUST"
quote = '''
An application that is able and wishes to receive PTB messages MUST
perform ICMP validation as specified in Section 5.2 of [BCP145].
'''

[[spec]]
level = "MUST"
quote = '''
A validated PTB message MAY be used
as input to the DPLPMTUD algorithm but MUST NOT be used directly to
set the PLPMTU.
'''